ABSTRACT
Abstract The influence of black polyethylene mulching on the evapotranspiration losses of irrigated sweet pepper (Capsicum annuum L.) was studied in an inland area of central Italy during the growing seasons 1996 and 1997. The influence on the agronomic length of the cycle, the crop yield and quality was also considered, comparing the results of plots with and without mulching. Reductions in water losses of 92 and 84 mm (28.3 and 24.3%) were measured for the mulched treatment in the first and the second year respectively. The total amount of such reductions, as well as the distribution during the growing cycle, has been observed to be connected with the seasonal evolution of the climate and the related crop response. The influence of mulching on the evapotranspiration rate is greater in the early vegetative period, when the crop cover is negligible. The 68% (63 mm) and the 49% (42 mm) of the total reduction of the irrigation water has been measured from transplanting to 10% of soil cover in 1996 and 1997 respectively. Such distributions are due to the different climatic conditions under which the crop developed. Fully satisfactory productions have been obtained in both years, without significant differences between treatments. A 10 days advance in harvest time was allowed by mulching in 1997. Keywords. Crop response, evapotranspiration, irrigation agronomy, microlysimeters, mulching, black polyethylene, rainfall, water saving.
